Perimenopausal risk of falling and incidence of distal forearm fracture.

A postal survey of 2000 women and 2000 men sampled from the electoral roll in Oxford was undertaken to ascertain whether changes with age in the risk of falling might explain the stepwise increases in age specific incidence rates of distal forearm fracture which occur in women at around the age of 50. Corrected response rates were 83% for women and 72% for men. In women, but not in men, there was a rise in the risk of falling from 45 years, peaking in the 55-59 year age group, and sinking to a nadir at ages 70-74. In both sexes rates rose in extreme old age. These variations were not attributable to preferential response from people who had suffered a fracture. It is concluded that changes in the risk of falling interact with osteoporosis to produce a perimenopausal rise in the incidence of forearm fractures and contribute to the fluctuations in incidence of these fractures in old age.     

Validity of hamstring muscle length assessment during the sit-and-reach test using an inclinometer to measure hip joint angle

The aim of this study was twofold: (i) to describe the criterion-related validity of the sit-and-reach test (SRT) using a hand-held inclinometer when assessing hamstring muscle length (HML) when HML is recorded in degrees of hip joint angle (HJA); and (ii) to describe the effect of gender and age on HML in healthy adults during the performance of a SRT. We examined 212 healthy subjects (106 men and 106 women) whose ages ranged from 20 to 79 years. The Pearson-product moment correlation coefficient (r) described the relationship between HJA at the end-point of the SRT and the criterion, supine passive straight-leg raise (PSLR). We conducted a 6 x 2 analysis of variance, where age was stratified on 6 levels of 10-year increments (20-29, 30-39, 40-49, 50-59, 60-69, and 70-79 years of age) and gender was stratified on 2 levels (men and women). There was a statistically significant correlation (r = 0.59, P < 0.01) between performance on the SRT as measured by HJA and the supine PSLR, but the SRT only accounted for 35% of the variability in the PSLR. SRT performance in men (mean +/- SD, 80 +/- 9 degrees) was significantly less (P < 0.001) than in women (mean +/- SD, 92 +/- 10 degrees). Subjects in the 60- to 69- and 70- to 79-year age groups had significantly less (P < 0.05) HJA than those in the 20- to 29-, 30- to 39-, and 40- to 49-year age groups. Using an inclinometer to measure HJA during the SRT is not a valid method for assessing HML in men and women who can independently assume a long-sitting position on a hard surface. Clinicians should recognize there are differences in HML between men and women, and that men and women between 20 to 49 years of age have more HML than their counterparts between ages 60 to 79 years.     

Differences in the postexercise threshold for cutaneous active vasodilation between men and women

The purpose of this study was to evaluate the possible differences in the postexercise cutaneous vasodilatory response between men and women. Fourteen subjects (7 men and 7 women) of similar age, body composition, and fitness status remained seated resting for 15 min or cycled for 15 min at 70% of peak oxygen consumption followed by 15 min of seated recovery. Subjects then donned a liquid-conditioned suit. Mean skin temperature was clamped at approximately 34 degrees C for 15 min. Mean skin temperature was then increased at a rate of 4.3 +/- 0.8 degrees C/h while local skin temperature was clamped at 34 degrees C. Skin blood flow was measured continuously at two forearm skin sites, one with (UT) and without (BT) (treated with bretylium tosylate) intact alpha-adrenergic vasoconstrictor activity. The exercise threshold for cutaneous vasodilation in women (37.51 +/- 0.08 degrees C and 37.58 +/- 0.04 degrees C for UT and BT, respectively) was greater than that measured in men (37.33 +/- 0.06 degrees C and 37.35 +/- 0.06 degrees C for UT and BT, respectively) (P < 0.05). Core temperatures were similar to baseline before the start of whole body warming for all conditions. Postexercise heart rate (HR) for the men (77 +/- 4 beats/min) and women (87 +/- 6 beats/min) were elevated above baseline (61 +/- 3 and 68 +/- 4 beats/min for men and women, respectively), whereas mean arterial pressure (MAP) for the men (84 +/- 3 mmHg) and women (79 +/- 3 mmHg) was reduced from baseline (93 +/- 3 and 93 +/- 4 mmHg for men and women, respectively) (P < 0.05). A greater increase in HR and a greater decrease in the MAP postexercise were noted in women (P < 0.05). No differences in core temperature, HR, and MAP were measured in the no-exercise trial. The postexercise threshold for cutaneous vasodilation measured at the UT and BT sites for men (37.15 +/- 0.03 degrees C and 37.16 +/- 0.04 degrees C, respectively) and women (37.36 +/- 0.05 degrees C and 37.42 +/- 0.03 degrees C, respectively) were elevated above no exercise (36.94 +/- 0.07 degrees C and 36.97 +/- 0.05 degrees C for men and 36.99 +/- 0.09 degrees C and 37.03 +/- 0.11 degrees C for women for the UT and BT sites, respectively) (P < 0.05). A difference in the magnitude of the thresholds was measured between women and men (P < 0.05). We conclude that women have a greater postexercise onset threshold for cutaneous vasodilation than do men and that the primary mechanism influencing the difference between men and women in postexercise skin blood flow is likely the result of an altered active vasodilatory response and not an increase in adrenergic vasoconstrictor tone.     

Psychrometric limits and critical evaporative coefficients for unacclimated men and women.

Critical environmental limits, defined as those above which heat balance cannot be maintained for a given metabolic heat production, have not been determined for unacclimated subjects. To characterize critical environmental limits and to derive evaporative heat exchange coefficients (K(e)') for unacclimated young men (n = 11) and women (n = 10), subjects of average aerobic fitness walked at 30% maximal aerobic capacity in an environmental chamber. Critical environmental conditions were defined as the psychrometric loci of dry-bulb temperature and water vapor pressure at which core (esophageal) temperature was forced out of equilibrium (heat gain exceeded heat loss). Compared with the men in our study, the women had significantly higher critical environmental limits (P < 0.001) in warm (34-38 degrees C), humid (>60%) environments, a function of their lower absolute metabolic heat production at the fixed relative exercise intensity. Isotherms constructed from biophysical models closely fit the data in this range of environments but underestimated empirically determined critical limits in hotter, drier environments. Sex-specific values of K(e)' were derived by partial calorimetry in the critical water vapor pressure environments, in which full skin wettedness occurred. There were no sex differences for K(e)' (men = 17.4, 15.5, and 14.2 W. m(-2). Torr(-1) and women = 16.8, 15.5, and 14.2 W. m(-2). Torr(-1) at 34, 36, and 38 degrees C, respectively). These K(e)' values were lower than those previously published for fully heat-acclimated men (18.4 W. m(-2). Torr(-1) at 36 degrees C) and women (17.7 W. m(-2). Torr(-1) at 36 degrees C and 15.5 W. m(-2). Torr(-1) at 38 degrees C) and may be used to model heat balance responses for unacclimated men and women working in hot environments.     

Evaluation of the use of an integration-type laser-Doppler flowmeter with a temperature-loading instrument for measuring skin blood flow in elderly subjects during cooling load: comparison with younger subjects

An integration-type laser-Doppler flowmeter, equipped with a temperature-load instrument, for measuring skin blood flow (ILD-T), and analytical parameters developed in a previous study were used to compare changes in the skin blood flow in the forehead and cheek in elderly subjects (in their 60s and 70s) with those in younger subjects (in their teens to 50s). Age-related differences in skin blood flow in the forehead and cheek in response to cooling were evaluated in 90 healthy women in their teens to 70s (mean age: 17.2 +/- 0.33 years for teenagers; 24.3 +/- 0.76 years for those aged 20-29 years; 34.8 +/- 1.12 years for those aged 30-39 years; 43.3 +/- 0.78 years for those aged 40-49 years; 53.8 +/- 1.13 years for those aged 50-59 years; 63.5 +/- 0.55 years for those aged 60-69 years; 72.2 +/- 0.70 years for those aged 70-79 years). The measurement was performed continuously for 5 min: for 1 min at a sensor temperature of 30 degrees C, for 2 min after the setting of the sensor temperature had been changed to 10 degrees C, and for 2 min after the temperature setting had been cancelled. The parameters analyzed were (1) skin temperature in a resting state before measurement ( T(rest)), (2) mean skin blood flow in 1 min at a sensor temperature of 30 degrees C ( F(30 degrees C)), (3) minimum skin blood flow at a sensor temperature of 10 degrees C ( F(min)), (4) slope of the blood flow plot during the period from the beginning of cooling at 10 degrees C to F(min) ( S(fall)), (5) time required for the sensor temperature to reach 10 degrees C (Delta t(s)), (6) maximum skin blood flow during the period from the end of cooling to the end of measurement ( F(max)), (7) slope of the blood flow plot during the period from F(min) to F(max) ( S(rise)), (8) rate of decrease of the skin blood flow during cooling: FDR = ( F(min)/ F(30 degrees C))x100, (9) recovery rate of the skin blood flow after the end of cooling: FRR = ( F(max)/ F(30 degrees C))x100. When correlations among the above nine parameters were evaluated by combining all age groups, significant correlations ( P < 0.01) were observed between F(30 degrees C) and F(min), F(30 degrees C) and F(max), F(30 degrees C) and S(fall), F(min) and F(max), and F(max) and S(rise) in the forehead. In the cheek, significant correlations ( P < 0.01) were observed in all these combinations except between F(max) and S(rise). When these analytical parameters were compared among the age groups, F(30 degrees C), T(rest), F(max), and S(rise) decreased significantly ( P < 0.02 for F(30 degrees C) and T(rest), P < 0.01 for F(max) and S(rise)) and S(fall) increased significantly ( P < 0.03) in the forehead with aging. However, no significant change with aging was observed in FDR, Delta t(s), F(min), and FRR. In the cheek, FDR increased significantly ( P < 0.03), and S(rise) decreased significantly ( P < 0.01) with aging. However, no significant change with aging was observed in F(30 degrees C), T(rest), F(max), S(fall), Delta t(s), F(min), and FRR. Thus, the decrease in the skin blood flow during cooling showed no marked quantitative change with age, but, with aging, the rate of this decrease was clearly reduced in the forehead. In the cheek, on the other hand, the skin blood flow decreased markedly with aging, but no clear change was observed in the rate of this decrease. By using ILD-T and examining various parameters obtained, the skin hemodynamics in the forehead and cheek during cooling from 30 degrees C to 10 degrees C could be analyzed, and differences in the hemodynamics between the forehead and cheek and between elderly and younger individuals were clarified. This instrument is expected to be clinically useful.     

Dispersal of boll weevils (Coleoptera: Curculionidae) from cotton modules before ginning

We characterized the level of risk of boll weevil, Anthonomus grandis grandis Boheman, reintroduction to an eradication zone posed by dispersal from cotton modules during and after transport to the gin. Mark-release-recapture experiments in August and September in Texas indicated that most weevils disperse rapidly from the module surface, temperature permitting, unless confined under a module tarp, where most died. Nevertheless, 1-5% of released weevils were recovered alive after 24 h on the side and top surfaces of modules, representing potential dispersants. Mortality of boll weevils caged on the top surface of a module was 95-100% after 1-4 d when maximum air temperatures were > or = 33 degrees C and 72-100% when minimum temperatures were -7 degrees C or lower, but a few survived even after experiencing a minimum daily temperature of -12 degrees C. Under warm (daily maximum temperatures > or = 25 degrees C) and cold (daily minimum temperatures < or = 0 degrees C) weather conditions, survival was higher under the tarp than on the open surface of the module (20 versus 7% and 42 versus 26%, respectively), but mortality was 100% in both locations when temperatures reached 34 degrees C. Our results indicate that although the threat to an eradication zone posed by boll weevil dispersal from an infested module is very low under most environmental conditions, it is probably greatest when 1) a module is constructed and transported from an infested zone during weather too cool for flight, followed by warm weather favorable for flight at the gin yard; or 2) such a module is transported immediately after construction in moderate-to-warm weather.     

Comparison of thermoregulatory responses between men and women immersed in cold water.

Eleven women (age = 24.4 +/- 6.3 yr, mass = 65.0 +/- 7.8 kg, height = 167 +/- 8 cm, body fatness = 22.4 +/- 5.9%, mean +/- SD) were immersed to neck level in 18 degrees C water for up to 90 min for comparison of their thermal responses with those of men (n = 14) in a previous similarly conducted protocol. Metabolic rate increased about three times resting levels in men and women, whereas the rate of rectal temperature cooling (DeltaT(re)/Deltat) in women (0.47 degrees C/h) was about one-half that in men. With use of all data, DeltaT(re)/Deltat correlates with the ratio of body surface area to size and the metabolic rate of shivering correlates inversely to the square root of body fatness. No significant gender differences in total metabolic heat production normalized for body mass or surface area were found among subjects who completed 90 min of immersion (9 women and 7 men). Nor was there a gender difference in the overall percent contribution ( approximately 60%) of fat oxidation to total heat production. Blood concentrations of free fatty acids, glycerol, beta-hydroxybutyrate, and lactate increased significantly during the 90-min immersion, whereas muscle glycogen sampled from the right quadriceps femoris vastus lateralis decreased (free fatty acids, glycerol, and beta-hydroxybutyrate were higher in women). When the subjects were subgrouped according to similar body fatness and 60 min of immersion (6 women and 5 men), no significant gender differences emerged in DeltaT(re)/Deltat, energy metabolism, and percent fat oxidation. These findings suggest that no gender adjustments are necessary for prediction models of cold response if body fatness and the ratio of body surface area to size are taken into account and that a potential gender advantage with regard to carbohydrate sparing during cold water immersion is not supported.     

Thermal adjustment to cold-water exposure in resting men and women

Thermoregulatory responses were studied in 10 men and 8 women at rest in air and during 1-h immersion in water at 20, 24, and 28 degrees C. For men of high body fat (27.6%), rectal temperature (Tre) and oxygen consumption (VO2) were maintained at air values at all water temperatures (Tw). For men of average (16.8%) and low (9.2%) fat the change in Tre (delta Tre) was inversely related to body fat at all Tw with VO2 increasing to 1.07 l X min-1 for a -1.6 degrees C delta Tre for lean men. For women of average (25.2%) and low (18.5%) fat Tre decreased steadily during immersion at all Tw. The greatest changes occurred at 20 degrees C with little differences in delta Tre and VO2 noted between these groups of women. In comparison with males of similar percent fat, Tre dropped to a greater extent (P less than 0.05) in females at 20 and 24 degrees C. Stated somewhat differently, lean women with twice the percentage of fat have similar delta Tre as lean men at all Tw. For delta Tre greater than -1.0 degree C men showed significantly greater (P less than 0.05) thermogenesis compared with women. The differences in thermoregulation between men and women during cold stress at rest may be due partly to the sensitivity of the thermogenic response as well as the significant differences in lean body weight and surface area-to-mass ratio between the sexes.     

Has mortality from melanoma stopped rising in Australia? Analysis of trends between 1931 and 1994.

OBJECTIVE--To describe recent trends in mortality from melanoma in Australia. DESIGN--An analysis of trends in age standardised and age and sex specific mortalities by year of death and median year of birth (cohort). SETTING--Australia. SUBJECTS--All deaths from melanoma registered in Australia between 1931 and 1994. RESULTS--Melanoma mortality rose steadily from 1931 to 1985. From 1959 the annual rate of increase was 6.3% in men and 2.9% in women, resulting in mortalities of 4.82 and 2.51 per 100,000 person years in 1985 and 1989, respectively. Mortalities for both sexes seem to have plateaued from June 1985 onwards. In 1990-4 the rate rose by 3.7% in men to 5.00 per 100,000 and in women it fell by 5.2% to 2.38 per 100,000. The non-significant increase after 1985 in mortality in men was restricted to those aged over 70 years of age, whereas the fall in rates in women was mostly in those aged under 55 years. This pattern was generally reflected in the state trends, though with some variation: rates for women in Queensland had peaked in the late 1970s; while rates for men in New South Wales continued to rise in 1990-4, placing them above those for Queensland. Examination of mortalities specific for age, period, and cohort for Australia as a whole showed several salient features. Rates in men rose steeply in cohorts born before about 1930; were stable in cohorts born between 1930 and 1950; and fell in more recent cohorts. Rates in women showed similar changes but about five years earlier. CONCLUSION--Melanoma mortality in Australia peaked in about 1985 and has now plateaued. On the basis of trends in cohorts it can be expected to fall in coming years.     

Flexibility of the shoulder joint measured as range of abduction in a large representative sample of men and women over 65 years of age

In a representative survey of 1000 elderly men and women aged over 65 years living in their own homes, assessments have been made of flexibility measured as range of shoulder abduction in addition to health status, psychological well-being and reported customary activity. The results for shoulder abduction were approximately normally distributed and the mean values (+/- 1 standard deviation) were as follows: - in men aged 65-74 years, 129 (+/- 14) degrees and aged over 74 years, 121 (+/- 19) degrees; in women aged 65-74 years, 124 (+/- 19) degrees and aged over 74 years, 114 (+/- 22) degrees. These mean values are about 30 degrees less than those accepted for younger subjects. Nearly half the distribution falls below the accepted threshold level of 120 degrees for adequate function. There were significant effects of sex and age (P less than 0.001); women had poorer flexibility and the reduction with age amounted to 10 degrees per decade. Multiple regression analysis showed that the effect of age was accounted for in part by health, strength and customary use. The effects of use were most marked in those with some disability. This suggests that maintained or increased use could offset some of the age-related loss of the range of shoulder movement.     

Maximal oxygen uptake of agricultural men and women in India

The maximal oxygen uptake (VO2 max) of 228 men and 47 women from the Indian agricultural community was measured. The VO2 max in 20-24-year-old men was about 17% less than in the 25-29-year-old group. With advancing age, the VO2 declined gradually to the ages 55-59, excepting the 36-39-year-old group. The loss in VO2 max was 0.65 ml/kg.min per year between 25 and 39 years of age and 0.16 ml/kg.min per year between 40 and 59 years of age. However, 30-39-year-old women had 7% higher VO2 max than the 20-29-year-old age group; and the difference in VO2 max between the group 30-39 and the group 40-49 years of age was 32%. The 20-29-and 40-49-year-old women had VO2 max 24 and 30% less than those of men in the same age range.     

Effect of high-intensity interval training on cardiovascular function, VO2max, and muscular force

The purpose of this study was to examine the effects of short-term high-intensity interval training (HIIT) on cardiovascular function, cardiorespiratory fitness, and muscular force. Active, young (age and body fat = 25.3 ± 4.5 years and 14.3 ± 6.4%) men and women (N = 20) of a similar age, physical activity, and maximal oxygen uptake (VO2max) completed 6 sessions of HIIT consisting of repeated Wingate tests over a 2- to 3-week period. Subjects completed 4 Wingate tests on days 1 and 2, 5 on days 3 and 4, and 6 on days 5 and 6. A control group of 9 men and women (age and body fat = 22.8 ± 2.8 years and 15.2 ± 6.9%) completed all testing but did not perform HIIT. Changes in resting blood pressure (BP) and heart rate (HR), VO2max, body composition, oxygen (O2) pulse, peak, mean, and minimum power output, fatigue index, and voluntary force production of the knee flexors and extensors were examined pretraining and posttraining. Results showed significant (p < 0.05) improvements in VO2max, O2 pulse, and Wingate-derived power output with HIIT. The magnitude of improvement in VO2max was related to baseline VO2max (r = -0.44, p = 0.05) and fatigue index (r = 0.50, p < 0.05). No change (p > 0.05) in resting BP, HR, or force production was revealed. Data show that HIIT significantly enhanced VO2max and O2 pulse and power output in active men and women.     

Age-related changes of vertebral bone mineral density in Russian population]

Vertebral trabecular bone mineral density (BMD) was measured by quantitative computed tomography (QCT) in 1061 subjects (610 females and 451 males aged from 7 to 91 and from 12 to 89, respectively) with known history of diseases or taking medicines affecting bone metabolism. Peak BMD values in our patients were observed at the age of 20-29 years with further gradual decrement in men and more steep in women. Negative relationship between BMD and age was r = -0.991 for men and r = -0.968 for women. Analyzing BMD changes by decades we observed the largest decrement in men after 60 (13.1% for 60-69 and 14.1% for 70-79 years of age) and in women after 50 (22.5% for 50-59, 22.1% for 60-69 and 20.8% for 70-79 years) which was most probably due to decline in sex hormones production that is known to significantly influence bone metabolism. This was confirmed by BMD values three-phase approximation in women showing the lowest rate of calcium loss by trabecular bone in reproductive period (1.9 mg/cm3/yr) and the highest in perimenopause (3.98 mg/cm3/yr). Annual calcium loss in postmenopause was 2.22 mg/cm3.     

Influences of age and gender on human thermoregulatory responses to cold exposures

To delineate age- and gender-related differences in physiological responses to cold exposure, men and women between the ages of 20 and 29 yr and 51 and 72 yr, wearing minimal clothing, were exposed at rest for 2 h to 28, 20, 15, and 10 degrees C room temperatures with 40% relative humidity. During the coldest exposure, the rates of increase in metabolic rate (W X m-2 or ml X kg lean body mass-1 X min-1 were similar for all groups. However, older women (n = 7) may have benefited from a larger (P less than 0.05) early metabolic (M) increase (40% within 15 min) than young men (18%) (n = 10), young women (5%) (n = 10), or older men (5%) (n = 10). A similar rapid M response in older women occurred during the 15 degrees C exposure. During all cold exposures, older women maintained constant rectal temperature (Tre) and young women maintained Tre only during the 20 degrees C exposures, whereas Tre of the men declined during all cold exposures (P less than 0.01). Changes in Tre and mean skin temperature (Ts) during cold exposure were largely related to body fat, although age and surface area/mass modified the changes in men. The data suggest that older men are more susceptible to cold ambients than younger people, since they did not prevent a further decline in their initially relatively low Tre. Despite greater insulation from body fat, the older women maintained a constant Tre at greater metabolic cost than men or younger women.     

Body temperature changes in dogs exposed to varying effective temperatures

Adult male and female Beagle dogs (eight total) were exposed individually, in series, to each of 23 effective temperatures for a period of 2 hours or until rectal temperature increased 1.1 degrees C. Rectal temperature was measured to the nearest 0.1 degree C by thermistor probes in the pre-test condition (basal temperature) and at each 5-minute interval during the test conditions (effective temperatures between 21.1 degrees C and 34.7 degrees C). The frequency at which dogs displayed a 1.1 degree C rise in rectal temperature was related to the magnitude of the effective temperature. At an effective temperature of 32.6 degrees C or greater, 100% of the dogs displayed a 1.1 degree C rise in rectal temperature. Between an effective temperature of 29.3 degrees C and 31.4 degrees C, some animals displayed a 1.1 degree C rise while others did not. At an effective temperature of 28.4 degrees C or below no animals displayed a 1.1 degree C rise. The mean time necessary for a 1.1 degree C rise was negatively correlated (P less than 0.01) to the magnitude of the effective temperature. The minimum effective temperature necessary to increase rectal temperature by 1.1 degree C in male Beagles (29.6 +/- 1.0 degree C) was not significantly different from females (30.8 +/- 0.4 degrees C).     

Aging and assessment of physiological strain during exercise-heat stress

The purpose of this study was to evaluate the physiological strain index (PSI) for different age groups during exercise-heat stress (EHS). PSI was applied to three different databases. First, from young and middle-age men (21 +/- 2 and 46 +/- 5 yr, respectively) matched (n = 9 each, P > 0.05) for maximal aerobic power. Subjects were heat acclimated by daily treadmill walking for two 50-min bouts separated by 10-min rest for 10 days in a hot-dry environment [49 degrees C, 20% relative humidity (RH)]. The second database involved a group (n = 8) of young (YA) and a group (n = 7) of older (OA) men (26 +/- 1 and 69 +/- 1 yr, respectively) who underwent 16 wk of aerobic training and two control groups (n = 7 each) who were matched for age to YA and OA. These four groups performed EHS at 36 degrees C, 40% RH on a cycle ergometer for 60 min at 60% maximal aerobic power before and after training. The third database was obtained from three groups of postmenopausal women and a group of 10 men. Two groups of women (n = 8 each) were undergoing hormone replacement therapy, estrogen or estrogen plus progesterone, and the third group (n = 9) received no hormone replacement. Subjects were over 50 yr and performed the same EHS: exercising at 36 degrees C, 40% RH on a cycle ergometer for 60 min. PSI assessed the strain for all three databases and reported differences were significant at P < 0.05. This index rated the strain in rank order, whereas the postacclimation and posttraining groups were assessed as having less strain than the preacclimation and pretraining groups. Furthermore, middle-aged women on estrogen replacement therapy had less strain than estrogen + progesterone and no hormone therapy. PSI evaluation was extended for men and women of different ages (50-70 yr) during acute EHS, heat acclimation, after aerobic training, and inclusive of women undergoing hormone replacement therapy.     

The effect of age and smoking on vascular prostaglandin production in men and women

6-Keto-PGF1 alpha, PGF2 alpha and PGE2 production by homogenates of aorta was unaffected by age, sex or smoking habits. Homogenates of saphenous vein from women aged 51-60 years produced greater and smaller amounts of 6-keto- PGF1 alpha and PGF2 alpha, respectively, than from women aged 41-50 and 61-70 years. In the 41-50 and 61-70 age groups, the amounts of 6-keto-PGF1 alpha and PGF2 alpha produced by homogenates of saphenous vein were smaller and greater, respectively, in women than in men. Cigarette smoking had no effect on PG production by homogenates of female saphenous vein. 6-Keto-PGF1 alpha production by homogenates of male saphenous vein was 20% lower in smokers and ex-smokers than in non-smokers, although this reduction was statistically significant only for ex-smokers. The amounts of PGE2 and PGF2 alpha produced by homogenates of male saphenous vein were smaller in smokers and ex-smokers, respectively, than in non-smokers. In spite of these changes in PG production by homogenates of saphenous vein, the basal outputs of PGs, particularly of 6-keto-PGF1 alpha, from the saphenous vein were little affected by age, sex or smoking habits.     

Genetic and environmental influences on expression of recurrent headache as a function of the reporting age in twins.

To explore age-related mechanisms in the expression of recurrent headache, we evaluated whether genetic and environmental influences are a function of the reporting age using questionnaire information that was gathered in 1973 for 15- to 47-year-old Swedish twins (n = 12,606 twin pairs). Liability to mixed headache (mild migraine and tension-type headache) was explained by non-additive genetic influences (49%) in men aged from 15 to 30 years and additive genetic plus shared environmental influences (28%) in men aged from 31 to 47 years. In women, the explained proportion of variance, which was mainly due to additive genetic effects, ranged from 61% in adolescent twins to 12% in twins aged from 41 to 47 years, whereas individual specific environmental variance was significantly lower in twins aged from 15 to 20 years than in twins aged from 21 to 30 years. Liability to migrainous headache (more severe migraine) was explained by non-additive genetic influences in men, 32% in young men and 45% in old men, while total phenotypic variance was significantly lower in young men than in old men. In women, the explained proportion of variance ranged from 91% in the youngest age group to 37% in the oldest age group, with major contributions from non-additive effects in young and old women (15-20 years and 41-47 years, respectively) and additive genetic effects in intermediate age groups (21-40 years). While total variance showed a positive age trend, genetic variance tended to be stable across age groups, whereas individual specific environmental variance was significantly lower in adolescent women as compared to older women.     

Effects of environmental cooling on force production in the quadriceps and hamstrings

The purpose of this study was to determine the effects of environmental cooling on force production in the quadriceps and hamstring muscles. Ten men (mean +/- SD: age = 21.4 +/- 2.2 years, height = 168.5 +/- 35.9 cm, body mass = 78.0 +/- 6.4 kg) participated in this study. Each subject completed 2 sets of 10 maximal effort repetitions on a Cybex II isokinetic dynamometer at 3.14 rad x s(-1). Between sets, subjects sat in environmental temperatures of 20, 15, 10, or 5 degrees C for 40 minutes. A significant decrease (p 相似文献   

Quantification of apolipoprotein D in human urine by zone immunoelectrophoresis assay: a methodological and clinical study.

A zone immunoelectrophoresis assay (ZIA) has been developed for the quantification of apolipoprotein D (apo D) in unconcentrated native human urine. A standard curve, linear between 1 and 8 mg apo D/l was obtained with ZIA. The relative coefficients of variation for this method were 5-9% (n = 15 x 6) with a mean +/- SD of 7 +/- 1.4% and below 11% (n = 6 x 15) for within-run and between-run reproducibility, respectively. Equal amounts of apo D in unconcentrated and diluted urines, in serum and of the purified protein produced the same zone migration distances indicating parallelism between the immunologic reactions of apo D in different sample matrixes. Storage experiments with normal urines demonstrated good stability of apo D in both acidic and alkalinized urine over at least 2 days at +5 degrees C and during several days at -20 degrees C to -40 degrees C. Using ZIA, urine samples from 50 normal healthy men aged 23-65 years were analyzed for apo D. Mean and SD were: 2.8 +/- 2.1 mg/l, 2.6 +/- 1.8 micrograms/min and 0.24 +/- 0.13 mg/mmol for concentration, rate of excretion and mass/creatinine concentration, respectively.